The present invention relates to brushes and, more particularly, to improved rotary brushes of the annularly or spirally arranged brush strip type which are primarily adapted for heavy duty such as brushing paved streets, sidewalks, concrete flooring and the like although brushes for other purposes may be similarly constructed.

Heretofore, brush strips have been devised which generally comprised individual bristles arranged in a row bound together by a flexible strip. Such brush strips were costly to fabricate and could not Withstand rough usage.

Accordingly, an object of the present invention is to provide brush strips for rotary brushes which are economical to manufacture and durable and thus are not subject to the foregoing difficulties and disadvantages.

Another object is to provide such brush strips which can be arranged on and secured to rotatable structure in a simple and practical manner.

Another object is to provide such brush strips which can be produced in various shapes and sizes depending upon their intended use.

A further object is to provide such brush strips which can be fabricated from a wide selection of materials.

A still further object is to provide such brush strips which readily can be modified for introducing sprays of water or other cleaning solutions between the brushing elements of the strips.

Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

In accordance with the present invention, the foregoing objects are generally accomplished by providing a rotary brush comprising rotatable structure, a brushing element formed of a unitary strip of yieldable plastic material annularly arranged on the structure, the strip having a lengthwise extending base and having vane means extending outwardly from the base and formed with a tip at the outer end thereof to effect brushing, and means for mounting and securing the strip on the structure in a manner to wind up the strip upon rotation of the structure.

The brush strip may be formed by molding or extruding and cutting operations; and may be formed of plastic materials including natural or synthetic rubbers or synthetic plastic resins which are tough and yieldable, for example, vinyl type resins, polyethylene, nylon, Teflon, cellulose acetate and the like.

In the drawings:

FIG. 1 is a fragmentary perspective view of a disc type rotary brush illustrating one embodiment of the present invention.

FIG. 2 is a fragmentary perspective view of a drum type rotary brush illustrating another embodiment of the present invention.

FIG. 3 is an enlarged sectional view illustrating one form of vane construction.

FIG. 4 is a view similar to FIG. 3 illustrating another form of vane construction.

FIG. 6 is a view similar to FIG. 3 illustrating an arrangement for introducing sprays of water between the vanes.

Referring now to FIG. 1 of the drawings in detail, there is shown a rotary brush comprising rotatable structure such as a circular disc 10 having a hub 11 for connection to a rotary drive shaft, and a brushing element 12 mounted and secured to the disc 10 in the manner hereinafter described. The brushing element 12 is formed of one or more unitary strips 14 of yieldable plastic material annularly arranged on the disc. For example, three adjacent concentric circular strips made to utilize as shown, although it will be understood that, in a brush having a large number of annular strip portions, a single strip 14 could be spirally arranged to provide adjacent convolutions. Thus, the expression annularly arranged as used herein and in the claims is intended to include both the circular and spiral arrangements of the brush strip.

In FIG. 2, a rotary brush is shown which comprises rotatable structure such a a hollow cylindrical drum 15 adapted to be mounted for rotation and driven by conventional means (not shown) and a brushing element 12 mounted and secured to the drum 15 in the manner hereinafter described. The brushing element 12 is formed of one or more unitary strips 14 of yieldable plastic material annularly arranged on the drum. For example, a single strip 14 is spirally arranged on the drum 15 to provide a plurality of adjacent convolutions, although it will be understood that a desired number of individual strips could be circularly arranged on the drum.

As shown in FIGS. 1 and 2, the brush stri s 14 have a lengthwise extending base 16, generally T-shaped in cross-section to provide flanges 17 at the sides thereof, and have lengthwise extending vane means 18 extending outwardly from the base 16. The vane means may comprise one or more elongate formations 19, for example four as shown, having a tip 20 at the outer end which serves as bristles to effect brushing in the illustrative embodiment, the vane formations 19 are arranged in side by side adjacent rows which fan or diverge so that the outer rows are closely adjacent or mesh with the outer rows of an adjacent strip portion to provide effective brushing action.

Preferably, the vane formations 19 are slit or separated crosswise to provide lengthwise extending rows of bristles as shown in FIGS. 1 and 2. However, only certain rows of formation may be so slit to provide relatively stiff rows and more flexible rows of brushing tip. For example, as shown in FIG. 3, the outer rows are slit and the inner rows are continuous; and, as shown in FIG. 4, the inner rows are slit and the outer rows are continuous. Thus, it will be appreciated that any desired combination of slit and continuous rows could be employed and that all or none of the rows could be slit or continuous.

The tips or working ends 20 of the formations may be flat as shown or may be tapered or curved in any desired manner.

The brush strips 14 are secured to the rotatable struc ture in any desired manner. For example, the base 16 may be adhesively secured by epoxy resin 21 or the like. Likewise, the flanges 17 may be formed with lengthwise spaced apertures 22 extending therethrough for received screws, bolts or rivets 24 adapted for securernent to the disc 16 (FIG. 1) or to the drum 15 (FIG. 2). The advantage of such an arrangement is that a damaged strip or section thereof can be removed and replaced by a length of new brush strip.

In FIG. 5, an arrangement is shown wherein the sides of the flanges of adjacent brushing strip are united to provide a more rugged and unitary brushing element. This is accomplished by providing a male formation 25 at one side of the base and a female formation 26 at the Q opposite side adapted to interengage but permit relative sliding movement therebetween in an annular direction. For example, the female formation may be a groove having a restricted entrance and the male formation may be a bead adapted to be sprung into the groove and be locked therein.

Such interlocking means may be advantageously employed in certain types of brush strip arrangements wherein a single strip 14 is spirally wound. For example, when the strip is arranged as shown in FIG. 2, only the ends of the strip need be secured to the rotatable structure because rotation of the brush element in the selected direction will tend to wind or wrap up the spiral to simulate an integral drum-like structure, whereby the drum 15 is not required. In such an arrangement, a pair of rotatable end collars mounted on drive means would suffice as the rotatable structure. Also, by omitting the drum, the brush element can bend or yield in a lateral direction about its axis of rotation that is, in a direction away from its axis of rotation to enable the brush to pass over bumps or humps on the surface to be brushed without damage to bristle formations or sacrificing brushing efiiciency by raising the brush while passing over bumps or the like.

In order to further facilitate assembly and securement of the brush strips 14 on and to the rotatable structure, the strips are fabricated in a manner to provide them with a preformed circular or spiral shape. That is particularly advantageous where the strips are to be wound on a small radius or are formed of a material which is not bent into shape as easily as other materials after fabrication of the strips.

In FIGURE 6, a brush strip 14 is shown which has conduit means such as a passageway 30 extending lengthwise therethrough and being provided with outlet means 31 spaced lengthwise and arranged to direct sprays of water or the like between adjacent rows of vanes. In such an arrangement, one end of the passageway would be closed or connected to a line for returning water to a reservoir and the other end of the passageway would be connected to a source for supplying water under pressure.

It will be understood that the brush strips shown in FIGS. 4 and 5 could be provided with a similar arrangement for directing Water between the vanes, either between all the adjacent vanes or only between the two rows of vanes at the middle of the base 16.

From the foregoing description, it will be seen that the present invention provides an improved brush strip and rotary brush adapted to be made in any desired size including such sizes suitable for heavy duty brushing.

As various changes may be made in the form, construction and arrangemnt of the parts herein, without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in any limiting sense.

I claim:

1. A rotary brush comprising rotatable structure; and a brushing element formed of a single unitary strip of spirally preformed yieldable plastic material arranged as a spiral on said structure with the convolutions of the spiral adjacent each other, said strip having a base formed with a surface facing said structure and with a pair of parallel opposite side and having integrally formed vane means extending outwardly from said base provided with a tip at the outer end thereof to effect brushing, said base stantially uniform dimensions throughout the length of said strip for uniting adjacent strip convolutions against lateral separation and permitting relative sliding movement between adjacent convolutions, whereby upon rotation of said structure in a given direction the spiral tends to be Wound up to form a rugged unitary brush structure.

2. A brush according to claim 1, wherein the spiral has the shape of a hollow cylinder and only the end convolutions of the spiral are supported on said rotary structure whereby said cylinder yields between its ends in a direction away from the axis of said rotatable structure.

3. A brush according to claim 2, wherein said supporting structure is driven from one end thereof.

4. A brush according to claim 1, wherein said female formation is a groove 'having a restricted entrance and said male formation is a bead disposed in said groove and has a web extending through said opening for connecting said head to the side of said strip. 5. A brush according to claim 1, wherein the crosssection of said base is a T-shaped block, the cross of the T provides said sides, and said vane means extend outwardly from the stem of the T.

6. A brush according to claim 5 wherein said vane means includes a plurality of parallel rows of diverging vanes.

7. A brush according to claim 6, wherein certain said vanes are separated crosswise along the length thereof to provide bristles.

S. A brush according to claim 7, wherein at least four vanes are provided and the two outer vanes are separated to form bristles.

*9. A brush according to claim 7, wherein at least four vanes are provided and the two inner vanes are separated to form bristles.

10. A brush according to claim 1, wherein said vane means includes a plurality of parallel rows of vanes, and said base has conduit means extending lengthwise therethrough and being provided with outlet means spaced along the length thereof for directing sprays of liquid between said rows of vanes.

11. A brush according to claim 10, wherein said outlet means are at the middle of said base.

12. A brush according to claim 10, including four rows of vanes and outlet means between adjacent rows of vanes.